Jim decides to leave his tribal area to seek his fortune in Johannesburg. As soon as he arrives, three gangsters mug him. When he regains consciousness, a friendly night watchman takes care of him. With the watchman's help, Jim gets a job in a nightclub as a waiter.

Zonk! shows the extraordinary cultural range available to township Africans, from the many ethnic strains of music from South Africa itself to contemporary American jazz and popular music, eagerly copied and Africanised.